Shear-mode PMN-PT piezoelectric single crystal resonator for microfluidic applications

We report on the integration of a PMN-PT single crystal-based piezoelectric resonator in a microfluidic system. In this experiment, the resonator was implanted in the microfluidic channel through a standard soft lithography process with its top electrode in contact with the flowing fluid. The results showed that, activated in shear mode, the resonator sensed changes occurring along the fluid-electrode interface and gave responses in the form of impedance resonance frequency shift. By measuring the frequency shift, changes in the fluidic property (e.g. viscosity) could be monitored. Examples are given to demonstrate the potential use of the system for cell detections.